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Studies on Synthesis of Stationary Phase Containing Nicotinamide Adenine Dinucleotide(NAD) Bonded to Phospholipid-Coated Aminated Silica for HPLC

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Chinese Chemical Letters 1997年第3期8卷 243-246页

作者： Jin Mao YOU Zong Qin RUAN jing wu kang (Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000) Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences 730000 China

Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids. In this paper, a series of synthetic reactions of solid-liquid phase were carried out on silica surface, using a macroporous(30 mu m), microspherical silica (8 mu m) as the matrix and gamma-aminopropyltriethoxysilane as the activating agent, the nicotinamide adenine dinucleotide(NAD) was bonded through its amino groups to the carboxylic groups of linked phospholipid which was bonded covalently on aminated support. The bonded stationary phase has high thermal stability, and could be used to separate of nucleotides with good resolution.

关键词： NAD Bonded to Phospholipid-Coated Aminated Silica for HPLC Studies on Synthesis of Stationary Phase Containing Nicotinamide Adenine Dinucleotide

Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： jing He Le kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect *** RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation

The chemical structures,biosynthesis,and biological activities of secondary metabolites from the culinary-medicinal mushrooms of the genus Hericium:a review

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Chinese Journal of Natural Medicines 2024年第8期22卷 676-698页

作者： QI Jianzhao wu jing kang Shijie GAO jingming Hirokazu Kawagishi LIU Hongwei LIU Chengwei Key Laboratory for Enzyme and Enzyme-Like Material Engineering of Heilongjiang College of Life ScienceNortheast Forestry UniversityHarbin 150040China Shaanxi Key Laboratory of Natural Products&Chemical Biology College of Chemistry&PharmacyNorthwest A&F UniversityYangling 712100China Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Fungal phytochemicals derived from higher fungi,particularly those from the culinary-medicinal genus Hericium,have gained significant attention in drug discovery and *** review aims to provide a comprehensive analysis of the chemical structures,biosynthetic pathways,biological activities,and pharmacological properties of monomeric compounds isolated from Hericium *** the past 34 years,253 metabolites have been identified from various Hericium species,including cyathane diterpenes,alkaloids,benzofurans,chromenes,phenols,pyrones,steroids,and other miscellaneous *** investigations into the biosynthesis of erinacines,a type of cyathane diterpene,have led to the discovery of novel cyathane *** research has highlighted the biological activities and pharmacological properties of Hericium-derived compounds,with particular emphasis on their neuroprotective and neurotrophic effects,immunomodulatory capabilities,anti-cancer activity,antioxidant properties,and antimicrobial *** A,in particular,has been extensively ***,transcriptomic,and proteomic analyses of Hericium species have facilitated the discovery of new compounds and provided insights into enzymatic reactions through genome *** diverse chemical structures and biological activities of Hericium compounds underpin their potential applications in medicine and as dietary *** review not only advances our understanding of Hericium compounds but also encourages further research into Hericium species within the realms of medicine,health,functional foods,and agricultural *** broad spectrum of compound types and their diverse biological activities present promising opportunities for the development of new pharmaceuticals and edible products.

关键词： Hericium Secondary metabolites Biological activity Biosynthesis

Intestinal tuberculosis with small bowel stricture and hemorrhage as the predominant manifestation: Three case reports

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 248-256页

作者： Gang Huang kang-kang wu Xiao-Na Li jing-Hua Kuai Ai-Jun Zhang Department of Gastroenterology Qilu Hospital(Qingdao)Cheeloo College of MedicineShandong UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Intestinal tuberculosis is a chronic disease caused by Mycobacterium tuberculosis that mainly affects the ileum and *** bowel tuberculosis,characterized by predominant involvement of the small intestine,is an extremely rare condition with highly atypical clinical presentations,making diagnosis even more *** SUMMARY We report three cases of small intestinal tuberculosis,two of the patients pre-sented primarily with abdominal pain,and one presented with gastrointestinal *** patients underwent blood tests and imaging *** bowel endoscopy(SBE)revealed that the main lesions in these patients were in-testinal stenosis or gastrointestinal bleeding caused by small intestinal *** patient ultimately underwent surgical *** a complex diagnostic process and comprehensive analysis,all patients were confirmed to have small intestinal tuberculosis and received standard antituberculosis treatment,leading to an improvement in their *** Patients with SBTs present with nonspecific symptoms such as abdominal pain,weight loss,and occasional gastrointestinal *** diagnosis requires a thorough evaluation of clinical symptoms and various tests to avoid misdiagno-sis and complications.

关键词： Intestinal tuberculosis Gastrointestinal hemorrhage Small bowel endoscopy Case report

Two Monte Carlo-based simulators for imaging-system modeling and projection simulation of flat-panel X-ray source

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Nuclear Science and Techniques 2024年第7期35卷 31-46页

作者： Meng-Ke Qi Ting He Yi-Wen Zhou jing kang Zeng-Xiang Pan Song kang Wang-Jiang wu Jun Chen Ling-Hong Zhou Yuan Xu School of Biomedical Engineering Southern Medical UniversityGuangzhou510515China State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou510275China Department of Radiotherapy Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou510515China

The advantages of a flat-panel X-ray source(FPXS)make it a promising candidate for imaging *** imaging-system modeling and projection simulation are critical for analyzing imaging performance and resolving overlapping projection issues in *** conventional analytical ray-tracing approach is limited by the number of patterns and is not applicable to FPXS-projection ***,the computation time of Monte Carlo(MC)simulation is independent of the size of the patterned arrays in *** study proposes two high-efficiency MC projection simulators for FPXS:a graphics processing unit(GPU)-based phase-space sampling MC(gPSMC)simulator and GPU-based fluence sampling MC(gFSMC)*** two simulators comprise three components:imaging-system modeling,photon initialization,and physical-interaction simulations in the ***-system modeling was performed by modeling the FPXS,imaging geometry,and *** gPSMC simulator samples the initial photons from the phase space,whereas the gFSMC simulator performs photon initialization from the calculated energy spectrum and fluence *** entire process of photon interaction with the geometry and arrival at the detector was simulated in parallel using multiple GPU kernels,and projections based on the two simulators were *** accuracies of the two simulators were evaluated by comparing them with the conventional analytical ray-tracing approach and acquired projections,and the efficiencies were evaluated by comparing the computation *** results of simulated and realistic experiments illustrate the accuracy and efficiency of the proposed gPSMC and gFSMC simulators in the projection calculation of various phantoms.

关键词： Flat-panel X-ray source(FPXS) Imaging-system modeling Projection simulation Monte Carlo-based simulators

Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： kang CUI Lin jing Ruisong JIANG Longnv YU Xiao GAO Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02%.In addition,the core shift prediction is also validated,with a prediction error of less than 26.9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

Adaptive Graph Convolutional Adjacency Matrix Network for Video Summarization

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Computers, Materials & Continua 2024年第8期80卷 1947-1965页

作者： jing Zhang Guangli wu Shanshan Song School of Cyberspace Security Gansu University of Political Science and LawLanzhou730000China

Video summarization aims to select key frames or key shots to create summaries for fast retrieval,compression,and efficient browsing of *** neural networks efficiently capture information about graph nodes and their neighbors,but ignore the dynamic dependencies between *** address this challenge,we propose an innovative Adaptive Graph Convolutional Adjacency Matrix Network(TAMGCN),leveraging the attention mechanism to dynamically adjust dependencies between graph ***,we first segment shots and extract features of each frame,then compute the representative features of each ***,we utilize the attention mechanism to dynamically adjust the adjacency matrix of the graph convolutional network to better capture the dynamic dependencies between graph ***,we fuse temporal features extracted by Bi-directional Long Short-Term Memory network with structural features extracted by the graph convolutional network to generate high-quality *** experiments are conducted on two benchmark datasets,TVSum and SumMe,yielding F1-scores of 60.8%and 53.2%,*** results demonstrate that our method outperforms most state-of-the-art video summarization techniques.

关键词： Attention mechanism deep learning graph neural network key-shot video summarization

A_(2)B_(7)-type La-Mg-Ni alloys prepared by Mg thermal diffusion for improved hydrogen storage performance

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Rare Metals 2024年第7期43卷 3260-3272页

作者： Yong-Xi Zhang Guan-Jiu wu jing Gu Hong-Xing kang Yuan Li Di Zhou Wen-Feng Wang Lu Zhang Shu-Min Han Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China Department of Chemistry and Biochemistry San Diego State UniversitySan DiegoCA92182-1030USA State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

A novel approach based on thermal diffusion was used to achieve controllable Mg content in A_(2)B_(7)-type La-Mg-Ni-based *** formation mechanism of the A_(2)B_(7)-type phase as a result of the thermal diffusion process and the effect of Mg content on hydrogen storage performance were investigated.X-ray diffraction(XRD)patterns and Rietveld refinement results showed that increased Mg transformed the LaNi_(5)phase in the La_(0.74)Sm_(0.03)Y_(0.23)Ni_(4.32)Al_(0.04)precursor alloy into a superlattice *** electron microscopy(SEM)images showed that Mg was evenly distributed in the alloy *** in the superlattice significantly inhibited the phase decomposition of the superlattice structure during the hydrogen absorption/desorption *** A_(2)B_(7)-type La_(0.57)Sm_(0.02)Y_(0.18)Mg_(0.23)Ni_(3.38)Al_(0.03)alloy composed of Gd_(2)Co_(7)and Ce_(2)Ni_(7)phases was successfully *** pressure-composition isotherm profiles showed that the alloy had a hydrogen storage capacity as high as 1.73 wt%,with good cycling *** 50 cycles of hydrogen absorption/desorption,the alloy retained a hydrogen storage capacity of 1.45 wt%,with a capacity retention rate of up to 84.28%.The Mg thermal diffusion process thus provides a new approach for the controlled preparation of La-Mg-Ni-based alloys.

关键词： La-Mg-Ni-based hydrogen storage alloy A_(2)B_(7)-type superlattice alloy Mg thermal diffusion process Phase transformation Hydrogen storage property

Major methods of seismic anisotropy

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Earthquake Research Advances 2024年第3期4卷 82-91页

作者： Xinai Zhao jing wu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China

Seismic anisotropy reveals that seismic wave velocity, amplitude, and other physical properties show variations in different directions, which can be divided into lattice-preferred orientation(LPO) and shape-preferred orientation(SPO) according to its physical mechanisms. The main methods for studying seismic anisotropy include shearwave splitting analysis, P-wave travel time inversion and surface-wave tomography, etc. There are some differences and correlations among these methods. Seismic anisotropy is an important way to reveal the dynamic processes of crust-mantle evolution, and it is significant for monitoring crustal stress changes and improve seismic exploration studies. With the help of long-term observation, the application of machine learning techniques and combining inversion based on multiple phases would become potential developments in seismic anisotropy studies. This may improve the understanding of complex seismic anisotropic models, such as multiple layers anisotropy with an oblique axis of symmetry.

关键词： Seismic anisotropy Shear-wave splitting P-wave travel time inversion Surface-wave tomography